The present invention relates to an improved intravenous feeding set and a measuring chamber for use therein.
Conventional intravenous feeding sets for feeding a parenteral solution directly into a patient's body often include measuring chambers for precisely controlling the amount of parenteral solution fed to the patient. A typical measuring chamber takes the form of a transparent plastic chamber marked with suitable indicia in order that the amount of fluid contained therein can be determined visually. The measuring chamber is usually inserted in the flow line of the intravenous feeding set immediately downstream of the parenteral solution supply bottle, upstream of the flow control means used for controlling the parenteral fluid flow rate, and upstream of any flow rate measuring means that may be employed in the system. A second flow control clamp is usually positioned upstream of the measuring chamber for controlling the flow of parenteral fluid passing from the supply bottle to the measuring chamber.
In using an intravenous feeding set with a measuring chamber, the measuring chamber, after priming of the system, is filled with the amount of parenteral solution to be fed to the patient, this being accomplished by visual reference to the indicia on the body of the chamber. Thereafter, the flow connection between the parenteral fluid supply bottle and the measuring chamber is shut off so that no additional fluid from the supply boottle will pass into the measuring chamber. Venipuncture is then accomplished and all the fluid in the metering chamber is allowed to flow into the patient's body.
In order that specific medication can be added to the parenteral solution as it is being fed to the patient, conventional intravenous feeding sets are often provided with one or more "injection sites." Such injection sites often take the form of a plastic or rubber nipple opening directly into the flow line of the intravenous set, the nipple being covered with a rubber cap which can be pierced by a conventional hypodermic needle. Usually conventional injection sites are positioned to communicate with a flow conduit in the intravenous feeding set so that the medication can be added to a stream of parenteral fluid as it flows through the conduit. Alternately, or additionally, an injection site may be formed directly in the top of a conventional measuring chamber so that the medication can be added directly to the fluid in the measuring chamber.
Measuring chambers including injection sites formed in their tops are disadvantageous in a number of particular areas. For example, because an injection site found in the top of a measuring chamber is upward facing, it tends to collect dust when used, which is objectionable from a health standpoint. Moreover, many attendants experience difficulty in reaching an upward facing injection site formed in a measuring chamber top once the intravenous feeding set is ready for operation since the measuring chamber is usually elevated high over the patient's head during normal use.
Still another disadvantage associated with injection sites formed in the tops of measuring chambers is that they are used with difficulty when it is desirable that the medication be administered to the patient uniformly mixed in the parenteral fluid. With an upward facing injection site formed in the top of a measuring chamber, this mixing is difficult to accomplish since the medication added from the top of the chamber does not significantly mix with the parenteral fluid already in the chamber. Also, the medication may become aerated on striking the parenteral fluid surface.
Yet another disadvantage associated with injection sites formed in the tops of measuring chambers concerns removal of parenteral fluid from the chamber. To remove fluid the parenteral fluid flow must be stopped and the measuring chamber inverted. After the fluid is removed, the flow line of the intravenous set must be rebled to avoid air bubbles in the line. This procedure is not only time consuming but may result in stopping up the intravenous needle.
Accordingly, it is an object of the present invention to provide an improved measuring chamber in which the injection site associated therewith has little tendency to collect dust in use.
It is a further object of the invention to provide an improved measuring chamber including an injection site which is easy to reach when the intravenous set carrying the measuring chamber is in an operating condition.
It is a still further object of this invention to provide an improved measuring chamber which enables additional medication added to be uniformly mixed with the parenteral fluid already in the chamber so that the medication can be fed to the patient uniformly along with the parenteral fluid.
Yet another object of the invention is to provide an improved measuring chamber which enables parenteral fluid to be removed without inverting the chamber and stopping the parenteral fluid flow.
Still another object of this invention is to provide an improved measuring chamber which is of simple construction, which is easy and inexpensive to manufacture by injection molding, and which is highly accurate.